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NFPA 13, 25 & 20 fire pump requirements. 1
- Thread starter micfinch
- Start date
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1
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SprinklerDesigner2
Mechanical
I copied and pasted your doc file below:
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I have some questions regarding the below fire pump sprinkler installation and testing requirements. The fire pump in question is a marine application.
1.Firstly, is it not true, that to ensure my pump is able to perform at 150% at no less than 65% of the rated head pressure I will need the TDH rating of the pump? I have looked for standard specifications of several centrifugal pumps on-line and this particular pump nameplate, the rated head is not listed on either. Is the max head pressure determined following the delivery performance curve calculations? Or it a specification I should have. I am trying to make sense of a recent service report indicating my installation was not able to perform at 150%. With no mention of the TDH, I don’t think that statement can be deduced accurately. One issue is that NFPA 25 (inspection) does not elaborate the “at no less than 65% max head” requirement, NFPA 20 (pump requirements) does.
2.NFPA 25, 8.3.3.2 requires the pump run at the no-flow condition (churn) for ½ hour. Is the purpose of this to ensure the pump does not overheat? Or, to test the circulating relieve valve, I see the circulating relive valve is required yet I fail to
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In order for a fire pump to be listed it must produce 150% of its rated capacity at 65% of its rated pressure. If it is red and has a UL and/or FM sticker on it the pump will give that performance at a minimum and, most likely, more.
Sounds like the pumps you are looking at are not listed fire pumps?
Not sure about NFPA #25 but I think it is both.
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I have some questions regarding the below fire pump sprinkler installation and testing requirements. The fire pump in question is a marine application.
1.Firstly, is it not true, that to ensure my pump is able to perform at 150% at no less than 65% of the rated head pressure I will need the TDH rating of the pump? I have looked for standard specifications of several centrifugal pumps on-line and this particular pump nameplate, the rated head is not listed on either. Is the max head pressure determined following the delivery performance curve calculations? Or it a specification I should have. I am trying to make sense of a recent service report indicating my installation was not able to perform at 150%. With no mention of the TDH, I don’t think that statement can be deduced accurately. One issue is that NFPA 25 (inspection) does not elaborate the “at no less than 65% max head” requirement, NFPA 20 (pump requirements) does.
2.NFPA 25, 8.3.3.2 requires the pump run at the no-flow condition (churn) for ½ hour. Is the purpose of this to ensure the pump does not overheat? Or, to test the circulating relieve valve, I see the circulating relive valve is required yet I fail to
------------------
In order for a fire pump to be listed it must produce 150% of its rated capacity at 65% of its rated pressure. If it is red and has a UL and/or FM sticker on it the pump will give that performance at a minimum and, most likely, more.
Sounds like the pumps you are looking at are not listed fire pumps?
Not sure about NFPA #25 but I think it is both.
8.3.3.2 The pertinent visual observations, measurements, and adjustments specified in the following checklists shall be conducted annually while the pump is running and flowing water under the specified output condition:
(1) At no-flow condition (churn):
(a) Check the circulation relief valve for operation to discharge water.
(b) Check the pressure relief valve (if installed) for proper operation.
(c) Continue the test for ½ hour.
(2) At each flow condition:
(a) Record the electric motor voltage and current (all lines).
(b) Record the pump speed in rpm.
(c) Record the simultaneous (approximately) readings of pump suction and discharge pressures and pump discharge flow.
(1) At no-flow condition (churn):
(a) Check the circulation relief valve for operation to discharge water.
(b) Check the pressure relief valve (if installed) for proper operation.
(c) Continue the test for ½ hour.
(2) At each flow condition:
(a) Record the electric motor voltage and current (all lines).
(b) Record the pump speed in rpm.
(c) Record the simultaneous (approximately) readings of pump suction and discharge pressures and pump discharge flow.
3.3.23.4 Total Rated Head. The total head developed at rated capacity and rated speed for either a horizontal split-case or a vertical shaft turbine–type pump.
6.2* Factory and Field Performance.
6.2.1 Pumps shall furnish not less than 150 percent of rated capacity at not less than 65 percent of total rated head.
6.2.2 The shutoff head shall not exceed 140 percent of rated head for any type pump.
8.1.2.2* The listing shall verify the characteristic performance curves for a given pump model.
8.1.2.2* The listing shall verify the characteristic performance curves for a given pump model.
The selection and application of the fire pump should not be confused with pump operating conditions. With proper suction conditions, the pump can operate at any point on its characteristic curve from shutoff to 150 percent of its rated capacity.
6.2* Factory and Field Performance.
6.2.1 Pumps shall furnish not less than 150 percent of rated capacity at not less than 65 percent of total rated head.
6.2.2 The shutoff head shall not exceed 140 percent of rated head for any type pump.
8.1.2.2* The listing shall verify the characteristic performance curves for a given pump model.
8.1.2.2* The listing shall verify the characteristic performance curves for a given pump model.
The selection and application of the fire pump should not be confused with pump operating conditions. With proper suction conditions, the pump can operate at any point on its characteristic curve from shutoff to 150 percent of its rated capacity.
A majority of the test equipment used for acceptance and annual testing has never been calibrated. This equipment can have errors of 15 to 30 percent in readings. The use of uncalibrated test equipment can lead to inaccurately reported test results.
While it is desirable to achieve a true churn condition (no flow) during the test for comparison to the manufacturer's certified pump test characteristic curve, it might not be possible in all circumstances. Pumps with circulation relief valves will discharge a small amount of water, even when no water is flowing into the fire protection system. The small discharge through the circulation relief valve should not be shut off during the test since it is necessary to keep the pump from overheating. For pumps with circulation relief valves, the minimum flow condition in the test is expected to be the situation where no water is flowing to the fire protection system but a small flow is present through the circulation relief valve. During a test on a pump with a pressure relief valve, the pressure relief valve should not open because these valves are installed purely as a safety precaution to prevent overpressurization during overspeed conditions.
While it is desirable to achieve a true churn condition (no flow) during the test for comparison to the manufacturer's certified pump test characteristic curve, it might not be possible in all circumstances. Pumps with circulation relief valves will discharge a small amount of water, even when no water is flowing into the fire protection system. The small discharge through the circulation relief valve should not be shut off during the test since it is necessary to keep the pump from overheating. For pumps with circulation relief valves, the minimum flow condition in the test is expected to be the situation where no water is flowing to the fire protection system but a small flow is present through the circulation relief valve. During a test on a pump with a pressure relief valve, the pressure relief valve should not open because these valves are installed purely as a safety precaution to prevent overpressurization during overspeed conditions.
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